An atomistic computer modeling investigation was made of the self-diffusion of Ti and Al along the interfaces of the lamellar L10 material. The interactions between the atoms were described by central-force many-body potentials, and the formation and migration of vacancies was considered. The interfaces studied were 3 types of γ/γ interface: ordinary twin, pseudo-twin, 120° rotational fault. For the latter 2 interfaces, diffusion was investigated for the stoichiometric case and for the case where the interfaces had a surplus of Ti; in the form of a layer having the composition and structure of Ti3Al. The calculations suggested that the diffusivity along γ/γ interfaces was higher than that in the bulk. The difference between the bulk and interfacial diffusivities was not as marked as in the case of grain boundaries. The surplus of Ti appeared to affect only marginally the interfacial diffusion.

An Atomistic Study of Interfacial Diffusion in Lamellar TiAl Alloys. M.Nomura, V.Vitek: Interface Science, 2003, 11[1], 99-109